The present invention generally relates to towed acoustic line array hoses and more particularly to a radially compliant towed acoustic line array hose which provides improved wear resistance and toughness without sacrificing radial compliance and flexibility.
Prior acoustic line array hoses were fabricated of either an extruded thermoplastic material or a composite of one or more cured elastomeric compounds reinforced longitudinally, and often radially, with high strength fiber materials.
Extruded thermoplastic hose materials used are usually a flexible grade of Polyvinyl Chloride (PVC) or Thermoplastic Polyurethane (TPU). Flexibility is required so as to obtain sufficient radial compliance associated with low self-noise as well as satisfactory coiling and handling characteristics at environmental temperatures. Line array sonars with extruded outer tubing of PVC or TPU alone in this flexibility range are not tough enough however to obtain an adequate service life with desired reliability. The main damage mechanisms causing failure of the tubing envelope are abrasion, puncture by sharp objects and cut-through at the edges of banding clamps and spacers. Such failures generally occur in service, particularly during deployment, handling and storage, thereby presenting a major reliability problem.
Reinforced elastomeric hoses, depending on the strength and orientation of the reinforcing fibers, while somewhat more resistant to banding clamp and spacer cut-through, are subject to abrasion, nicks, cuts and sometimes punctures by sharp objects, have lower radial compliance and are limited as to the continuous length able to be produced by the presently used mandrel-wrapping and curing process.